Early career, 1901–1903

Castle reported to the receiving ship USS Independence (1814) on 29 June 1901. Detached on 31 July 1901 to proceed to the Asiatic Station on board a United States Army Transport, he departed on 1 August 1901. Ultimately, he reported to armored cruiser USS Brooklyn (ACR-3) on 6 September 1901, but served in her only for a little over a month, being detached to battleship USS Kentucky (BB-6) on 11 October 1901.

His title changed from naval cadet to midshipman on 1 July 1902, Castle was ordered detached from Kentucky on 21 July 1902 to the gunboat USS Monocacy (1864), then to the gunboat USS Vicksburg (PG-11), reporting to Vicksburg on 30 July 1902 at Chefoo, China. Over the ensuing months, Vicksburg "showed the flag" and conducted training, steaming from Chinese to Korean, Japanese, and Philippine ports. Tensions between Japan and Russia occasioned Vicksburg's being dispatched to Chemulpo, Korea, where she arrived on 30 December 1903 to protect American interests there.

Chemulpo, 1904

Castle's promotion to ensign, retroactive to 7 June 1903, occurred on 5 February 1904, the same day that Japan and Russia broke off diplomatic relations. Soon thereafter, on 8 February 1904, the Japanese declared war upon Russia, beginning the Russo-Japanese War; that day, a fleet commanded by Japanese Rear Admiral Uriu Sotokichi arrived off Chemulpo, then landed troops. The following morning, the Japanese issued a challenge to the two Russian warships in port, the steel-hulled protected cruiser Variag and the gunboat Koretz, neither of which knew war had been declared, that the Japanese would attack the Russians where they lay unless they stood out of port by noon to do battle. The Russian ships began clearing for action at 9:00 a.m., then gamely stood out, to the cheers of the neutrals, the Japanese opening fire at about 11:50 a.m. Within a half-hour, Variag and Koretz retired toward Chemulpo, the Japanese ceasing fire at 12:40 to avoid endangering neutral shipping. Variag, badly damaged and afire, had suffered heavy casualties; British, French, and Italian warships sent boats with medical personnel to lend assistance. Vicksburg sent a whaleboat to do likewise. Castle's participation in that endeavor of mercy prompted Variag's commanding officer to present his personal sword to the young ensign in gratitude.

Surface ship duty, 1904–1907

Vicksburg returned to the United States on 29 June 1904, arriving at Bremerton, Washington, to be decommissioned. Detached from Vicksburg on 15 July 1904, Castle returned home with 30 days leave, upon the expiration of which he was to await orders to sea. On 12 August 1904, he received orders to the protected cruiser USS Chicago (1885), and reported aboard her on 22 August 1904. Detached on 28 October 1905, he reported to store ship USS Celtic (AF-2) on 30 October 1904, becoming her navigator on 21 November 1904, then her senior engineer on 1 February 1906. On 11 August 1906, he received simultaneous promotions to Lieutenant, junior grade and lieutenant.

Submarine duty, 1907–1909

Detached to command submarine USS Plunger (SS-2) ("a cross between a Jules Verne fantasy and a humpbacked whale [sic]," as one junior contemporary, Ensign Chester W. Nimitz, later described early submarines) on 22 February 1907, reporting for that duty on 23 February 1907 and assuming command upon her recommissioning at the New York Navy Yard in Brooklyn, New York. He received additional duty as commanding officer of USS Shark (SS-8) on 23 August 1907. Detached from Plunger to "continue other duties" (perhaps to devise means related to the envisioned transfer of "submarine torpedo boats" to the Asiatic Station as deck cargo on board colliers) on 24 December 1907, he then received orders to temporary duty at the Bureau of Navigation, reporting there on 25 April 1908, upon completion of which he was to travel to Mare Island Navy Yard at Vallejo, California, where he would have duty in connection with submarine USS Pike (SS-6). He reported on 13 May 1908, only to be detached on 1 July 1908 to travel to the Asiatic Station for duty with a draft of men, taking passage on 6 July 1908. He reported for duty on 4 August 1908 in connection with fitting out submarines USS Porpoise (SS-7) and Shark, both of which had been transported to Cavite Navy Yard on Luzon in the Philippine Islands as deck cargo on board the collier USS Caesar (AC-16).

Battleship duty, 1909–1910

Relieved on 9 July 1909 with new orders, Castle returned to the United States on 20 August 1909, reporting to battleship USS Ohio (BB-12) on 12 October 1909 to serve as her senior engineer officer. When Ohio was decommissioned a little over two months later, Castle received orders on 23 December 1909 to report without delay to battleship USS New Jersey (BB-16) for duty as her senior engineer officer, going on board New Jersey on 26 December 1909. He remained on New Jersey until detached on 6 August 1910.

Shore duty, 1910–1913

After detaching from New Jersey, Castle traveled to Pittsburgh, Pennsylvania, to be the assistant to the inspector of material, Carbon Steel Works, reporting on 10 August 1910. More shore duty followed, at his alma mater, when he arrived at the United States Naval Academy on 26 August 1910, where he would remain for almost three years, a period of time punctuated by additional temporary duty on board battleship USS Iowa (BB-4) during the midshipmen's summer cruise of 31 May 1911 to 11 September 1911, and in Philadelphia with the Brigade of Midshipmen on 25 November 1912.

Duty aboard USS Utah, 1913–1916

Detached from the Naval Academy on 7 June 1913, he arrived on board battleship USS Utah (BB-31) on 11 June 1913 to take up his duties as her ordnance officer.

Medal of Honor at Veracruz, 1914

Less than a year later, as tensions flared between the United States and Mexico, Castle commanded Utah's bluejacket landing battalion (consisting of 17 officers and 367 enlisted men), which landed at Veracruz on 21 April 1914 as part of the First Seaman Regiment. During the fighting that day and the next, Castle's conduct proved exemplary as he "exhibited courage and skill" in leading his men, "in seizing the Customs House [one of the principal objects of the landing] he encountered for many hours the heaviest and most pernicious concealed fire of the entire day 21 April 1914, but his courage and coolness under trying circumstances was marked ..." For his "distinguished conduct in battle," he received the Medal of Honor.^[1]

Shore duty, 1916–1918

Commissioned lieutenant commander on 15 September 1914, retroactive to 1 July 1914, Castle left Utah on 11 May 1916, reporting to the Bureau of Steam Engineering in Washington, D.C., on 13 May 1916. After serving as senior member of a board "to determine space and weight of various material features of submarine[s] to be built" on 20 July 1916, he later participated in the deliberations of the board that investigated and reported on the classification and standardization of motors on board ships on 21 November 1916. After a brief tour of temporary duty with Rear Admiral William S. Sims, during which he took passage in torpedo boat USS Wilkes (TB-35), Castle served on a board that evaluated "devices and plans connected with submarine warfare." On 31 August 1917, Castle received temporary promotion to commander.

Commanding officer, USS Martha Washington, 1918–1919

Ultimately, Castle's "urgent request" for World War I sea duty bore fruit. The Armistice with Germany that ended hostilities World War I, however, occurred on 11 November 1918, a week before his detachment from the Bureau of Steam Engineering on 18 November 1918 with orders to report to the receiving ship at New York Navy Yard. Arriving there on 22 November 1918, he relieved Captain Kenneth G. Castleman as commanding officer of the troop transport USS Martha Washington (ID-3019). Under Castle's command, Martha Washington conducted seven round-trip voyages to French, British, or Dutch ports, with New York City; Hampton Roads, Virginia, or Charleston, South Carolina, serving as the eastern termini.

Medal of Honor citation

Medal of Honor citation:

For distinguished conduct in battle, engagements of Vera Cruz, 21 and April 22, 1914. Eminent and conspicuous in command of his battalion, Lt. Castle was in the fighting of both days, and exhibited courage and skill in leading his men through action. In seizing the customhouse, he encountered for many hours the heaviest and most pernicious concealed fire of the entire day, but his courage and coolness under trying conditions were marked.^[3][4]

Namesake

A United States Navy destroyer to be named in Commander Castle's honor, USS Castle (DD-720), was authorized on 9 July 1942, and her keel laid on 11 July 1945. With the end of World War II in August 1945, construction was terminated on 11 February 1946 and she was delivered in a partially completed status to the 3rd Naval District on 15 August 1946. She was stricken from the Navy List on 2 November 1954 and sold incomplete for scrapping on 29 August 1955.^[5]